Process of treating hydrocarbons



United States Patent This invention relates to a process of improving hydro carbon stocks, such as lubricating oil stocks, asphalt stock-s, etc; by treatment thereof with a base in the pres ence of air, and to the resulting products obtained by this process.

Many of the commercially used lubricants are formed from hydrocarbon base stocks which are derived from natural sources, such as petroleum. For many purposes, so-called additives must be included with the hydrocarbon base stock in order to provide a lubricant having desirable characteristics, particulanly detergency. The solventextracted oils, for example, are generally provided with two additives or a multi-functional additive in order to impart corrosion inhibition and other desirable lubricant characteristics. The addition of these additives is associated with a higher cost of the finished lubricant. The preparation of a lubricant directly from the hydrocarbon base stock by chemically finishing or refining the entire stock to provide the wanted' properties at a commercially interesting cost has been a particularly bafiling problem.

Similarly, a number of additives have been developed for addition to asphalt to improve its properties, especially its adherence toaggregate. However, the preparation of an asphalt directly which has satisfactory adhesion has been an unsolved problem. v

It has been proposed heretofore that hydrocarbon base stocks be oxidized with the aid of oxidizing agents in the presence of air followed by neutralization. While such oils are useful, for instance, as soluble oils, they are unsatisfactory as lubricating oils since in many instances their oxidation instability is very great. The oxidized product may contain peroxides, whichflare' usually harm ful for engine use. Further, oxidized oils obtainedby such a process have a strong odor. e

In accordance with this invention, a hydrocarbon stock is treated with a base in the presence of oxygen. In the case of a lubricating stock the product has qualities de sirable in detergent lubricating oils. The products have a high detergency and surprisingly good oxidation stabil? ity, showing that the product is :difiererit from that result ing from the ordinary oxidation process: followed by neutralization. In the case of asphalt stocks' the product has better adhe'sivity. Evidently the process proceeds'in a somewhat diflere'nt' way, andlmay be characterized as a mild, controlled oxidation in an alkaline medium.

The reaction of thehydrocarbo'n basestoch with the base may be conducted With direct sdnnxtnre of the reactants or, if desired, by their admixture'intliepresence of a diluent which may be subsequently removed, but a diluent is not necessary. The reaction is usually complete in about two hours or less time, generally from one to two hours. The reaction time is a function of the temperature, the amount of oxygen, the amount ofbase'that is to react, the nature of the oil, the subdivision of the reactants, and the efiiciency of mixing. H

The hydrocarbon stock is reacted the base in any desired amount, depending on the weight ofthe stock. Desirably between about 0.5 and about 2% base would colloidal silica, clays; and thelike;

be used, where a clear product is desired. If a cloudy material can betolerated, then much more base can be used, e.g., 3% or more, and in fact there is no upper limit except that more than will react with the oil would not be used, of course. Generally at least about 1% should be used to achieve the beneficial properties due to increase in ash content, although smaller amounts show appreciable improvement.

If the hydrocarbon stock is relatively unreactive, it may be helpful to include a small amount of waterin the reaction mixture. Water increases the ash content of the stock, from which it is concluded that water increases the extent of the reaction with the oil. Any amount of water will improve the product but usually from 0.25 to 25% water would be used.

The treatment of the stock with the base is carried out in the presence of oxygen, and no definite upper limit can be placed on the amount of oxygen which is used although more oxygen would be used in the case of the more highly paraflinicstocks. Pure oxygen can be used, and also oxygen liberated from oxidizing agents, but air is preferred becauseof cost and ease of introduction into the reaction mixture, which can be regulated to suit the.

convenience and govern the foaming of the reaction mixture. In general, the more oxygen or air that is employed, the further. the reaction will proceed, and in the case of oils, the higher the ash content of the oil, until the limiting point when all of the components of the oil which are reactive with the base will have been taken up. This will vary with the oil. From 0.17 to 6 liters ofair per 1QO grams of oil per hour have been used with excellent results. If desired, inert gases such as hydrogen, nitrogen or carbon d ioxide can be blended with the oxygen or air, but this is not necessary. The reaction can be carried out under pressure, e.g., the pressure generated when a closed vessel is used.

The reaction temperature will vary to sometextentwith the hydrocarbonsto'clc Generally; the temperature of the reaction should be about 350 R, but should be beldw the temperature at which the reaction product would be decomposed and below the boiling point of the stock. This is a limitationon the lower boiling point of, the stock as well. A temperature of about 350 F. has been found in many cases to give an optimum improvement in the ash content of the 'oil and therefore is preferred. The treated oil is preferably centrifuged or filtered to remove slu dge and by-products. If a volatile diluent is used, it can be removed byevaporation.

The h 'drocarbon oil stock to which the process is applied can be any available hydrocarbon stock of low or high boiling point and low or high viscosity. The reaction temperature is established by the boiling point of the stock, and vice versa, to' minimize loss of volatiles, but low boiling stocks can be reacted as well under pressure to minimize this loss. If a high. viscosity material is disadvantageous, the viscosity can be cut by addition of a diluent; a e

Solvent-extracted and solvent-refined oils, i .e., oils treated inaccordance with conventional modern methods of solvent-refining lubricating oils, can be used when a product having lubricating properties. is desired'. As phalt stocks can be used in the production of asphalt cement, cutback asphalt, and asphalt emulsion bases having an increased ash content and, in many instances, an improved resistance to strippingj Lubricating oil stocks also can be used" in the production of greases using the oil treated in accordance' with the invention. In the preparation of such greases, smaller amounts of the gelling agent are required to thicken the oil to the'd sired grease'viscosity, particularly when inorganic gelling agents'are used, such asthejs'ilic-a' aerogels, fumed silica,

When the base is'a 3 lubricating oil stock, it may have a viscosity at 100 F. of to 500 centistokes, such as is used as the base for the SAE Nos. 10 to 50 oils. In addition the bright stocks having a viscosity up to 6000 SSUVat 100"v F. may be used. The oil maybe obtainedas a distillate or from 4 compound is not critical, and flake potassium hydroxide which contains 12% water is used in the examples.

In order to illustrate and point out some of the advantages of the invention, but in no sense as a limitation thereof, the following specific embodiments are included:

EXAMPLES 1 to 9 The hydrocarbon oils listedin the table below were reacted with 1.2% by weight of flake potassium hydroxide (containing 12% water) for 2 hours at 350 F. Throughout the reaction, nitrogeugas' was blown through the mixture The mixture was exposed to-air which may have been drawn in by the vortex action of the stirrer. The results were as follows;

Table I r Alkaline number Example Oil Aniline Percent. Percent 01) pH Pt, F. Yield SO4=Ash Strong Total 1 SAE No. lubr1- 97. 7 0. 905 17. 5 12. 82 1. 4. 99

eating oil, solventrefined. 2 Solventrextracted 255 92. 6 0. 884 23.2 12. 25 0. 4. 98

bright stock 78 SSU at 210 F. 3 Solvent-extracted 238 98. 1 0.884 4. 4 12.35 1. 38 4.12

neutral oil 300 SSU at 100 F. 7 4 Solvent-extracted 222 98. 1 0. 750 5.4 12.55 1. 30 3. 36 neutral oil 140 SSU V at 100 F. 5 A highly paraffinie 188. 7 95. 5 0, 650 6350 11. 95 O. 79 3. 95

hydrocarbon oil. 1 6 Acid-treated neutral 94.8 0.615 3920 13. 15 i 0. 94 3.68

red oil 300 SSU at 100 F. a V a 7 A light white 011 88. 7 0. 195 1. 6 11. 85 0.26 1. 13

' having a low prof r portion of aromatics 8-; Paraifin wax 96.2 0.005 Insoluble alone is blown throughthe mixture so that the amount of oxygen present is very limited. Oils which have a lower aromatic content, such as light white oil, andsimilar parafiinic oils, will react adequately if air is blown 7 through the mixture either with or Without nitrogen. An

ash-containing sludge which may form in some instances when the highly parafiinic oils'are reacted appears to be formed when aromatic oils are treated but does not precipitate because his more soluble in such oils. This is interpreted as meaning that the insoluble material is aromatic in nature. If soapy material is less soluble in the oil, then of coursethe final product will have a lower final ash content. I

A more highly aromatic oil for treatment can be obtained synthetically by recovering the aromatic fraction from other oils andblending it with'the stock to be treated in any desired proportion. V

Asphalt contains a high proportion of aromatics largely in the form of condensed rings. The preferred stock 'used in the process therefore should have at least some aromaticity, as distinguishedfrom aromatics-free stocks suchasparafiinwaxpf f The base employed is, any metal'compound reactive with hydrocarbon oils. The preferred metalcompounds are thoseof groups I, II and IILof the periodic table, such'as potassium, zinc,barium 'and aluminum, especially the and alkaline earth metals. The. hydroxides and oxidesof theselmetalsare-use'ful, but it may be pos-. sible in some instances alsdto use the sulfides,-'carbides, cyanamide s and other salts reactive with theIoiL. Sodium hydroxide, lithium hydroxide, lbarium hydroxide,l potassium hydroxide and potassium carbonate are. illustrative. Potassium hydroxide has been, used LinLlflakeLfQrmQin manyofthe following examples idor'dento' study. the e flect of other variables. 'Ijhe water, content of thebase These results show that the aromatic oils (solventrefined or lightly acid-treated) of Examples 1 to 4 and 6 are somewhat more reactive than the paraifinic oils with a low aromatic content, such as the oils of Ex amples S and 7.- Parafiin wax did not yield a soluble product.w However, adequate reactivity of all of the oils tested with the potassium hydroxide was obtained. Those oilswhich did not react as completely would react more completely if the amount of present were increased, in'other words, if at were blown through the mixture rather than nitrogen.

. To 600 grams of a light white oil was added 1.2% flake KOH (12% water) and the mixture reacted for 2. hoursat 350 F. During the reaction 2 /3 liters of air per grams ofoil per hour were blown through the mixtures The yield was 84% of a product (Example 9) having an OD of 1.8, a pH of 12.2, an alkaline number of 2.50and containing 0.425% ash.

These results show that some reaction with the light white oil is obtained when air is blown through the reactionrmixture. These results should be compared with Example 7, where very little reaction occurred in the absence of airblowing. g a a The products obtained in the above experiments were usefulgasgdetergent lubricating oil bases.

EXAMPLES 10 TO 15'- The following experimentswere carried out to show the efiect of potassium hydroxide concentration on the reaction; :A solvent-extracted neutral oil, 300 SSU at 100 .151, was employed. ,The, reaction time .was'2 hours, and the temperature .350 QF.; 'Ihe, reaction mixture was blown. with. nitrogen throughout, keeping the amount of air at a minimum. The amountof potassium hydroxide ake. 12% 1 l d as ns is d' nt e b -V Table II Alkaline Num- Percent Percent Percent ber Example KOH Yield S O =Ash D pH Strong Total 1 Centrifuged to remove insoluble material, not filtered.

These results show that when increasing amounts of potassium hydroxide were employed, more and more .insoluble material was formed. This insoluble material was soapy in nature, containing potassium, and resulted in a lower final ash content, showing the potassium was not going into the desired product. It is evident that no advantage from the standpoint of ash increase was ob-.

tained when more than 2% potassium hydroxide was used. The products obtained after reaction with 2, 3. and 5% potassium hydroxide were diflicult to filter but can be readily centrifuged.

It is thought that these insolubles appear because of R is evident that 8% potassium hydroxide does not represent the upper limit of amount of base which can be used with aromatic oils.

EXAMPLES 19 TO 23 The following examples were carried out to demonstrate the eifectiveness of various bases in the reaction of the invention.

-A solvent-extracted neutral oil, 300 SSU at 100 F. 600 g.) was employed. The reaction time was 2 hours and the reaction temperature was 350 F. The reaction mixture was blown with nitrogen throughout, keeping the amount of air at a minimum. The amount of base used was as indicated in the table:

' Table IV Percent Percent Alkalin Base Moles 1 Yield Ash OD pH N 0.

Flake KOH 0. 113 98.1 0.884 4. 4 12. 4. 12 Pellet KOH--- 0. 113 97. 2 0. 325 6. 5 11. 99 1. 55 K100 0. 113 93. 8 0. 305 89. 4 10. 17 1. 12 Pellet NaOH 0. 113 98.2 0.225 78. 5 9. 27 0.57 LlOH.HaO 0. 113 97. 3 0. 125 30. 0 9. 44 0. 49

1 690 g. 011 charge.

the presence in the oil of non-aromatic fractions which are poorer solvents for the soaps. than are the, aromaticoils. These results should be compared'with the results in the following examples.

EXAMPLES 16 TO 18 The following experiments were carried out with the aromatic fraction of a solvent-extracted neutral oil, 140 SSU at 100 F. This fraction was obtained by passing a pentane solution of the oil through silica gel, whereby the aromatics were adsorbed on the gel. The gel was eluted with benzene and the aromatic fraction obtained reacted with the amounts of the potassium hydroxide (flake, 12% H O) indicated in the table. The time of reaction was 2 hours and the temperature 350 F. The reaction mixture was blown with nitrogen throughout the reaction.

The results show that increasing the amount of potassium hydroxide in this case increased the ash content. This conlirms that the non-aromatic fractions are poorer solvents for the soaps formed by thereaction of the invention than are the more highly aromatic frac- These results show that potassium carbonate, sodium hydroxide and lithium hydroxide are effective since the products had a high pH and a relatively high alkaline number. The potassium carbonate most nearly approaches potassium hydroxide in eifectiveness but sodium hydroxide and lithium hydroxide also are satisfactory. The ash contents of these products are comparable. Flake potassium hydroxide (12% water) was the most effective of the bases used.

EXAMPLES 24 TO 26 The following experiments were carried out to show the effect of water during the course of the reaction. The base used was barium hydroxide containing varying amounts of water. A solvent-extracted neutral oil, 300 SSUat F., was used (600 grams). The reaction time was 2 hours andthe temperature 350 F. The re.- action mixture was blown with air (l liter per 100 grams of oil per hour) throughout'the-reaction time and then stripped by blowing with air at the rate of 2.67 liters per 100 grams of oil per hour. The amount of barium hydroxide used was as indicated in the table:

1 .11; strip ping, 2.673400 3. oil/hr.

tent.

. '7 8 The results show 'that the greater the amount'of water Thus it is evident that reaction time is a function of in the reaction mixture, the greater the extent of'thei'ereaction temperature (cf, Examples 27 to 30). 4 action. The ash eontent-ofthe product with the most W tsr .(Examnlefi) s1tsi i th s l er e $35 T042 Prepa'lfid Without. added Water (Example 24) and th 5 There action of potassium hydroxide with a solvental a n mbe s v 'fl the a as p the latterextracted 011, 300 SSU at 100 R, was studied is deter- Theidetergency also is greater.

. at 350 F. for 2 hours, using 1.2% potassium hydroxide To 5 p a and blowing with nitrogen throughout, with the introduc- These experimentsshow the influence, of reaction tem 9 tion of the amount of air indicated inthe tableiff 1'.

mine the influence of The reaction was carried out mt. V111 H Ainliters j AlkalinoNo.

Example Air, 1 per 100 Percent Percent OD pH a liters grams per Yield SO4=Ash hour V Strong Total 0 0 V 95.5 5 01070 31.0 10.96 0.00 0.24 2 0.105 90.9 0.285 215.7 12.19 0.10 1.01 4 0.33 97.0 0.505 14.5 a 12.00 0.15 2.70 s 0.66 95.7 0.515 20.8 10.94 0.20 2,88 16 1.33 95.8 0.575 11.5 12.21 0.40 4.04 32 2.66 02.5 0.820 10.0 12.62 0.50 49s 48 4.00 94.5 0:40 5.5 11.54 0.51 2.50 64 5. 32 93.8 0.34 75.4 11.55 0.26 1.45

perature. Potassium hydroxide (flake, 12% E 0) was 7 Example shows the results when no air is used. reacted with a solvent-extracted neutral oil, 300 SSU at Very little reaction occurred. When air was added to 100 F., for-2 hours. The amount of potassium hythe system, the amount of reaction increased propordroxide was 1.2% in each experiment, and the. reaction. 30,, tionately. The results establish 2.66 liters per 100 grams mixture was blown withnitrogen throughout. of. oilper hour as the optimum, since thereafter the ash v V c content decreased.

-TdhlaVl. 1 s a.

' 35 V EXAMPLES 43 TO 47 V a Alkalitne Num- Because of the general unsuitability of oxidized oils Example fifff 31555, '6 PH .FF'I it could 'not be predicted that the reaction product of I St the invention would possess qualities desirable in demng V V terg ent lubricating oils notwithstanding the high ash con- 5 tent. Test results using the Polyveriform Test as de- 222 32;; 8;{22 1 313 318% 182 8%? embed 1n Patent No. 2,464,233 were therefore run. 350 98.1 0.884 4-4 12-3 4- Although a corrosion and oxidation inhibitor would 99' 0560 13m 1 have to' be added, the results below show that .thepotas- X m d V sium hydroxide treatment has not adversely afiected the other'properties of thebase oil. This is unexpected inv f 7 p v V asmuch as products obtained by oxidizing oils using P shqw that thg P .18 a conventional oxidation process followed by neutraliza- 350 F' at Winch s m h Feacnon lsvessfcntiany tion are unsatisfactory as lubricating oils. This is shown complete after 2 hours. -At lower temperatures, a longer by Example inthetable below: 7 time would be required for completion. At higher tem- V 5 I peratures, the ash content appears to be slightly reduced. p i

T5515 2: .EXAMPLES 31 TO 34,,

Oilof Oilof Oxidized Oilof Oilof To show the importance of reaction time, 1.2% potas- V Example Example SAE 30 Example Example sium hydroxide was reacted with a solvent-extracted neup 1 (KtOdH- r 011 1: (Unia (KtOdH- tral oil, 300 SSU at 100 F., for-the time indicated in the ma. 6 we m r table. The reaction temperature was 350 F. and the 1' I 4 reaction mixture. was blown with mtrogen throughout. Examp 3 44 45 6 Cu-Pb corrosion,

V 00 mgms 19.3 28.9 30 7 227.4 82.4

r w Y r f V Vis. increase, ssu r a 5 as a: .25 eu. o a Time Percent Percent i b c r ii I d 57 0 21 5 97 0 6 o 029 S Example (hrs) Yield sol=xsh 01) 11 fig g A A 3 a strong Total Lacquer rating A A A A- A- at 0.5 A 97.3 "0.087' "1.1 11.01 7 0.00 055* a' 81222 ii 1 21% Example 44 is superior to 43 m oxidation stability 34:11:: 5.0 V 00.3 0.820 21.4 10." 0.0 5.02 (viscosity increase and neutralizatlon number). Example I 1, 1 4..-. n 70,,47,,is, superior to Example 46 in corrosion inhibition. In

' r 1 g n sneither 44 nor 47 are the other properties too adversely These re'sults show that the" reactionis essentially"oon aftected,

plete after 2 ho'ur's at 350 F. Further reaction for as 1 Example 45 was prepared from 30% of a lime-neulong as five hours tends actually toreduee thewash con 'Q iZeCLSAE No. 30 oil which had been oxidized for hours at 285 F. in the presence of 0.2% manganese Uversol (naphthenate) and 0.2% sodium carbonate. This oil was very p'oorin oxidation stability, evidenced by the high viscosity increase and neutralization number. This shows the treatment of the invention results in a reaction difierent from an oxidation. 7

These tests are not intended to show the detergency of the oil. They are intended to show only that the treatment does not adversely affect the properties measured by the Polyveriform Test.

In order to show the detergency of the oil it was subjected to a dispersancy test, which consists in determining the highest weight of carbon black which a 5% solution of the oil in benzene will hold in suspension. Thisftest is carried out as follows: A 5% by volume solution of the oil in benzene is prepared and 100 ml. of this solution is placed in a 100 ml. glass-stoppered graduate. 0.2 gram of carbon black is added and the graduate shaken for 15 seconds. The mixture then is observed in'front of a light source for a break point which marks the interface between the settled carbon particlesand thesuspension, and is seen as a thin layer of completely transparent liquid containing no carbon particles which travels down the graduate as the carbon particles settle. The graduate is allowed to stand for 5 minutes and the weight of carbon black increased by 0.2 gram additions each 5 minutes thereafter until a break point appears. The highest weight carbon black which does not produce a break point is a measure of the dispersancy.

In this test the oil of Example 33 had a dispersancy of 2.6. The untreated oil had a dispersancy of 0.2.

EXAMPLE 4s The following example illustrates the preparation of a grease employing an oil treated with potassium hydroxide in accordance with the invention.

The oil base stock used was a solvent-extracted neutral oil having a viscosity of 2,000 SSU at 100 F. The oil was reacted with 2% by weight of flake potassium hydroxide (12% Water) for 2 hours at 350 F. while blowing 1 liter of air per 100' grams of oil per hour through the reaction mixture. The product contained 0.74% ash and had a pH of 13.03 and an alkaline number of 4.39.

Two greases were prepared, one using the oil treated as set forth above and the other using the untreated oil according to the following formulation:

Table X Percent components: G. 9.0 Santocel ARD (silica aerogel) 72.0 0.9 Amine O, 1-[3-hydroxyethyl2-heptadecenyl imidazoline 7.2

1.0 Paratac, high molecular weight isobutylene polymer 8.0

0.5 Parafiow, a hydrocarbon wax naphthalene condensate of the Friedel-Crafts type 4.0

0.5 Ortholeum 300 3 a mixture of complex organic amines having both antioxidant and metal-deactivating properties 4.0 88.1 Oil (463-100) 704.8

Wis. at 210 F., s.s.u 1300 Flash point, F 400 lsaour 60/60 F ossi e C 3V1 V is. 210 E S.S.U 110 Flash point, F 450 Pour point, F 20 Conradson carbon, wt. percent 0.889 Specific gravity, 60/60 F .889

3 Appearance Melting range, F Miscibility with oils and greases In all proportions above 160 F.

The greases thus obtained were tested with the following results:

Inverted (sonpy). 5

The results show that a stiffer grease is obtained using the potassium hydroxide-treated oil in accordance with the invention. Thus, it is possible to use less silica aerogel to obtain a grease of comparable consistency usingthe oil treatedinaccordance jwith the invention.

EXAMPLE 49 Y Asphalt cement was reacted 'with 1.2% potassium hydroxide-(flake, l2% l-I O), for' 2 hours at 350 F. The reaction mixture was blown with nitrogen throughout. To remove unreacted potassium hydroxide, the mixture was allowed to stand for 1 hour at 350 F. and then decanted. The results were as follows:

Table XII Asphalt Cement Untreated KOH Treated pH 14. 74 Alkaline number:

Total 11. 69 Stripping test, percent coated 40 96 R & B softening point F.) 113 156 Pen at 77-100g.-5 sec. 78 33 Pen at 100 g.5 sec 226+ 72 Pen at 32200 g.60 se 23 18 Duct. at 775 cm./min 100+ 13 Duct. at 605 cm./min 65 5. 5

A true reaction with the base rather than a solution or dispersion was shown by the absence of carbon disulfide insolubles.

In order to take into account the decrease in penetration during reaction, a higher penetration asphalt would be used as a starting material to yield a final product of satisfactory penetration.

The asphalt cement showed high antistripping activity. The product remained 96% coated after the test.

In addition to the uses illustrated in the examples, the treated oils of theginvention are suitable bases for engine preservative oils, transformer oils and gear oils. The improved lubricants prepared from lubricating oil base stocks can be used in blends together with other lubricants or lubricant addition agents, e.g., with soap or the like in the grease, or with the addition of corrosion inhibiting lubricating oil additives for use as a lubricating oil. If desired, an agent for improving clarity can be added, for example lecithin, lauryl alcohol and the like. An agent for preventing foaming can be included, such as tetraamyl silicate, an alkyl orthocarbonate, orthoformate or orthoacetate, or a polyalkyl silicone oil.

The oils can also be used as cutting and grinding oils and as soluble oils. In these uses they are free from the characteristic odor of ordinary oxidized oils either before or after neutralization. They are thus not found objectionable by workmen using them with metal cutting machines where odor is a problem because the oil is exposed.

In view of the foregoing disclosure, variations and modifications of the invention will be apparent to those skilled in the art, and it is intended to claim such variations and modifications broadlyexcept as do not come within the scope of the appended claims.

. We claim: i

1. A method'of processing hydrocarbon base lubricating oil having aviscosity at .100". F. of frornlOto 500. centistokes to yield a product having ahigher as hcontent and a greater detergencywhich comprises'reacting the oil with an amount within the range from about 0510 about 3% by weight of the oilotastrongmetal baseselected jromthe group consisting oi metals of groups I and- II of theperiodic table at about 350 F. for a time sufiicient tojefiect reaction but less than two hours while blowing with nitrogen in the presence of oxygen. 2. A process in accordance with claim 1 in which the oil is a solvent-refined lubricating oil. 7

3; A process in accordance with claim 1 which includes blowing the reaction mixture with air during the reaction,

4. A process in'accordance with claim 1 in which the base is a potassiumbase. g ,7 j

5. A process in accordancewith claim 1 in which the base is a barium base. t

6. A method of processing hydrocarbon base lubricating oil having a viscosity'at 100 F. of from 10 to $00 centistokes to yield a product having a higher ash content and a greater detergency which comprises reacting the oiiwith an amount within therange from about 0.5 .to

about 3% 'by wcightjof the oil of flake. potassium hydroxide-at about 350 for about two hours, suflicient to efiect reaction, whileblowing with air in a volume within, the range from about 0.17 to about 6 liters per 100 grams of oil per hour.

References Cited in the file, of this patent UNITED STATES PATENTS Canada oer. 16,1951 

1. A METHOD OF PROCESS HYDROCARBON BASE LUBRICATING OIL HAVING A VISCOSITY AT 100*F. OF FROM 10 TO 500 CENTISTOKES TO YIELD A PRODUCT HAVING A HIGHER ASH CONTENT AND A GREATER DETERGENCY WHICH COMPRISES REACTING THE OIL WITH AN AMOUNT WITHIN THE RANGE FROM ABOUT 0.5 TO ABOUT 3% BY WEIGHT OF THE OIL OF A STRONG METAL BASE SELECTED FROM THE GROUP CONSISTING OF METALSL OF GROUPS 1 AND II OF THE PERIODIC TABLE AT ABOUT 350*F. FOR A TIME SUFFICIENT TO EFFECT REACTION BUT LESS THAN TWO HOURS WHILE BLOWING WITH NITROGEN IN THE PRESENCE OF OXYGEN. 